Ms Fredericks travelled more than 1400 kilometres from Biloela to Parliament House in Canberra on Wednesday.

She and fellow Biloela local Browyn Dendle carried a petition with more than 250,000 signatures urging the Morrison government to let the family stay.

The women wanted to meet with the prime minister and their local representative, Nationals MP Ken O'Dowd.

"We're just going to show them what the love of Australians can do," Ms Fredericks said.

"These are our friends, these are our people and they belong here."

Mr O'Dowd has already spoken to government ministers on behalf of the family.

But the Flynn MP said the Biloela locals had contacted his office on too short notice, so he was unable to see them on Wednesday.

The Tamil family of four are in detention on Christmas Island.

Last week, the Federal Court ruled the asylum-seekers cannot be deported until September 18.

Home Affairs Minister Peter Dutton has ruled out using his discretionary powers to allow the family to stay, claiming "the boats will restart" if he does.

But Ms Dendle pointed to Mr Dutton's previous exemptions for two European nannies.

"Not every French au pair that comes to Australia now stays, we haven't got a huge influx of French au pairs," Ms Dendle said.

"Mr Dutton has already shown that it won't set a precedent."

The family could remain in detention for months if the matter goes to a "full and final hearing" after September 18.

Ms Fredericks said the family had a traumatic week after the mother, Priya, hurt herself falling through a floor board in their room.

But she said they remained hopeful they would be allowed to stay in Biloela, where they were wanted, needed and loved.

Ms Fredericks said the petition was evidence of what the family meant to Australians.

Their legal case hinges on two-year-old Tharunicaa and her right to apply for a protection visa, based on claims she would be subjected to "serious harm" in Sri Lanka.

Despite being Australian-born, Tharunicaa is deemed an "unauthorised maritime arrival" under the Migration Act, which stipulates children of asylum seekers who arrive in the country by boat cannot apply for a visa.

A succession of courts ruled her parents Priya and Nades and four-year-old sister Kopika are not refugees and do not qualify for Australia's protection.

If the family is deported, the group said they would spend $100,000 raised in donations to fund legal advice on how to get them out of Sri Lanka.